228 G. A. BOULENGER ON 



than broad ; prefrontals forming a median suture ; l frontal as long as or shorter than 

 its distance from the end of the snout, i^ to 2 times as long as broad, narrower be- 

 hind than in front ; parietals if to 2 times as long as broad ; interparietal \\ to 2 

 times as long as broad ; occipital usually shorter than the interparietal, sometimes 

 nearly as long and a little broader, sometimes separated from it by one 2 or two 3 small 

 shields, or by the parietals meeting in the middle/ 3 supraoculars, first longer than 

 the second and in contact with the second loreal, third small and rarely 6 in contact 

 with the frontoparietal; 3, very rarely 4, superciliaries, second longest; granules 

 between the supraoculars and the superciliaries absent or reduced to one or two. 

 Nasal usually forming a very short suture with its fellow behind the rostral 6 and with 

 the anterior loreal above the postnasal ; 7 anterior loreal shorter than the second ; 4 

 upper labials, rarely 3* or 5, 9 anterior to the subocular, which is narrower beneath 

 than above. Temporal scales moderately large, rhombic or hexagonal, strongly 

 keeled ; one, two, or three large, keeled upper temporals, first very rarely l0 in contact 

 with the fourth supraocular ; a long and narrow tympanic shield. 



3 pairs of chin-shields," first or first and second in contact in the middle; 15 to 

 24 gular scales on the median line, anterior narrow, juxtaposed,, feebly keeled, then 

 increasing in size, imbricate, pointed, keeled, and merging gradually into the rather 

 indistinct collar, which is composed of 8 to 12 plates. 



Dorsal plates truncate and shortly mucronate behind, in 6 or 8 longitudinal 

 series on the neck, 4 or 6 on the anterior part of the body; 4, very rarely 6, in the 

 middle of the body, 4 on the lumbar region. 12 Ventral plates obtusely pointed and 

 shortly mucronate, strongly keeled, in 10 or 12 longitudinal and 21 to 28 transverse 

 series. A rather irregular series of large keeled scales borders the ventral plates 

 and is separated from the dorsals by a granular area. 28 to 38 plates and scales 

 round the middle of the body. Prseanal plate rather large, more or less distinctly 

 bicarinate, with smaller keeled plates on the sides. 



Upper surface of limbs with rhombic keeled scales. 1 or 2, very rarely 3, 

 femoral pores on each side. 13 Subdigital lamellae single or partly divided, 18 to 26 

 under the fourth toe, usually 21 to 26. 



1 Separated by one or two small shields in one specimen from Saigon and in another from Borneo. 



2 In one specimen from Borneo. 3 In one specimen from Saigon. 

 + Single specimens from S. China, Saigon. Rangoon and Java. 



6 One specimen from S. China, one from Saigon, and two from Great Natuna. 



s In single specimens from Ma Son Mts., Great Natuna, and Borneo, the rostral is narrowly in contact with the 

 frontonasal. 



I lu one specimen from Saigon the posterior portion of the nasal is detached to form a second postnasal ; the post- 

 nasal is absent on one side in a specimen from Matang. 



3 On both side in one specimen from Great Natuna and in one from Java ; on one side in one from Matang and in 

 one from Java. 



9 On one side in two specimens from Saigon and in one from Great Natuna. I0 In one specimen from Matang. 



II There are exceptions. Out of 25 specimens from Sikkim Stoliczka found 4 with 4 pairs and one with 3 shields on 

 one side and 4 on the other. Annandale found 2 with 4 pairs out of 27 from the Eastern Himalayas, Assam and Burma. 



12 There is sometimes irregularity on the two sides of the same specimen ; thus in a female from Siam there are 

 2 plates on one side and 3 on the other in the two transverse series of dorsal plates just before the middle of the body. 



13 Stoliczka's statement that they vary from 3 to 6 in Sikkim specimens requires' confirmation. The specimens on 

 which his description is based are not in the Calcutta Museum, Dr. Annandale informs me. 



